The present invention relates to industrial fasteners and more particularly to quarter-turn industrial panel fasteners which are used to removably secure two panels.
At the present time there are a number of commercially available industrial fasteners to secure two panels, and many such fasteners have been proposed in prior patents. The panels may be, for example, machine service or enclosure panels or container panels.
Generally, industrial fasteners of this type consist of two separated members one of which is attached to the first panel and the second of which is attached to the second panel. Such fasteners may be used to obtain a tight seal while allowing for quick access. Frequently, such fasteners are "quarter turn" fasteners which are locked by a 90.degree. turn and unlocked by a 90.degree. turn in the opposite direction. Some of these fasteners are "blind" fasteners which may be secured on the panels from one face of the panel without seeing its opposite face.
Two-member fasteners may be generally classified to be of one of two types. The first is a spring socket type in which the receptacle secured to one panel or formed as a spring in the panel grips and exerts a tension on the stud member, as is disclosed in U.S. Pat. No. 2,200,272 to Oddie; U.S. Pat. No. 2,413,510 to Luce; U.S. Pat. No. 2,334,676 to Jones; and U.S. Pat. No. 3,900,931 to Lavoillote.
An alternative general type of fastener, illustrated by U.S. Pat. No. 2,486,411 to Huelster; U.S. Pat. No. 3,136,017 to Preziosi; U.S. Pat. No. 2,975,667 to Bross; U.S. Pat. No. 3,675,280 to Winslade and U.S. Pat. No. 4,137,610 to Hoen, discloses spring-loaded stud members. However, some of the above-mentioned spring-loaded stud fastener patents also include spring retaining housings and most require the lateral stud projections to traverse a ramped receptacle for fastener tightening.
It has also been suggested that the turn member of an industrial fastener may be stamped from flat sheet metal, as in U.S. Pat. No. 3,900,931 to Lavoillotte.
Presently commercially available fasteners are satisfactory for many purposes. However, there is need for a quarter-turn blind fastener which is rugged, easily operable, simple, inexpensive and readily installed and which may be made from relatively low-cost materials without relatively expensive machining.